Typewriting machine



E. B. HESS.

TYPEWRITING MACHINE.

APPLICATION FILED APR 21. I922.

1,424,905. 7 Patented 8, 1922.

illlll EHIHII HHHHH E. B. HESS.

TYPEWRITING MACHINE.

APPLICATION Fl LED APR 21,1922.

1 424 9 5 I Patented Aug. 8, 1922.

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E. B. HESS.

TYPEWRITING MACHINE. APPLICATION FIILED APR 21.1922.

1,424,995, Patented Aug. 8, 1922.

3 SHEETS-SHEET 3.

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EDWARD B. HESS, OF NEW YORK, N. Y., ASSIGNOR TO ROYAL TYPEWRITER COMPANY, INC., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

TYPEWRITING MACHINE.

Specification of Letters Patent.

Patented Aug. 8, 1922.

Application filed April 21, 1922. Serial No. 555,853.

the following is a specification.

This invention relates to the platens of typewriting machines, and the object of the invention is to provide a supplemental or auxiliary platen which is associated with the main platen and which'can be brought into service when multi-manifolding is desired or when the, main platen is not sufiiciently hard or firm to produce'multimanifolds.

In my United States Patent No. 1,390,708

of Sept. 13, 1921, I have shown a typewriting machine in which the type action is such as to reduce the noise caused by the impact of the type bars on the platen and in such machines it is customary to use a relatively soft. cylindrical ,platen to assist in reducing noise, In these machines the number of copies which can be produced is somewhat limited although sutficient for ordinary purposes. I have now provided an auxiliary platen so associated with the main platen that the latter may be used for ordinary service even though relatively soft and the former may be quickly brought into active position when multi-manifolding is desired. In

this way I am enabled to use a relatively soft platen either with or without a noise reducing type action for ordinary service where only a few copies are required, but can quickly adapt the machine for multi-manifolding without removing the main platen or in any way modifying the mechanism.

In carrying out my present invention 1-- make little or no change in the construction in active position, the mainplaten provides a firm backing for the auxiliary platen, which latter has smooth inner and outer sides conforming to the shape of the main platen. By a simple operation the auxiliary platen may be brought from an inactive to the active position-or vice versa, and in order to hold the auxiliary platen in either position I provide detent mechanism of novel construction. The auxiliary platen is held in such close contact with the main platen that the former may be turned with the latter so that when the auxiliary platen is released from its detents it may be moved to active position by turning the main platen by means of its hand pieces or knobs, the friction between the two platens being sufficient to cause such movement. But the auxiliary platen may, if desired, be moved independently of the main platen. The construction of. the auxiliary platen is such that it may be used as an erasing .plate if desired and it may be formed with a letter space scale. Means is provided for preventing overthrow of the auxiliary platen when moved, in either direction and provision is made for limiting the movement of the detent pawls and for causing thestrain of the detent springs to be taken by the frame of the machine when the pawls are engaged with the detent members of the platen. Other features of the invention will be hereinafter explained.

In the accompanying drawings Figure 1 is a view on a large scale and in vertical section of the main platenwith the associated auxiliary platen. Some usual or ordinaryparts of a typewriting machine are also shown by way of illustration. The manner in which a large number of sheets for manifold purposes may be passed over the auxiliary platen is illustrated by the wide black line.

Figure 2 is a sectional View taken at the right hand end of the platen, the auxiliary platen being locked in an active position.

Figure 3 is a similar view, the section being taken near the left hand end of the1 00 platen, the auxiliary platen being locked in broken away showing how both members of the detent mechanism are connected'with the platens This figure of the drawings shows certain fractional spacing devices whichform no part of the present invention.

Figure 5 is a front view of a typewriter carriage carrying an ordinary platen and with the auxiliary platen shown in an actlve position across the line of print.

Figure 6 is a perspective view of the detent pawls employed at opposite ends of the platen and which are connected to move coincidentally.

Figure 7 is a perspective view showing how the auxiliary platen is mounted to turn about the longitudinal axis of the main platen and how it is provided with detent members for co-operation with the detent pawls.

Figure 8 illustrates how the auxiliary platen may be provided with a letter space scale.

Figure 9 shows the auxiliary platen in an inactive position with a type bar printing iIi the usual way with the main platen only as a backing.

I'n Figures 1 and 2, the type bar is shown as being connected to a noise reducing type action of the kind shown in my patent above mentioned, while in Figure 9 the type action is different. My improvements may be used in either type of machine. I

Most of the mechanism shown aside from the auxiliary platen and its detent mechanism is similar to that shown in most Royal machines. The main cylindrical .platen A is mounted in a carriage side frame-pieces of which are indicated'at B. The rail b of the carriage is supported by a shift rail C as I usual and the type bars-D are pivotally connected with a segment E and are operated by pull links d in the manner desrribed in my patent of Sept. 13, 1921 or in the usual way. A type bar guide is indicated at F, a ribbon guide or vibrator at G and paper feed mechanism at H. The upper feed rolls I are supported by rocker arms i as heretofore. In Figure- 5 a centrally located scale .J of usual construction is shown as are also end scales K. The features of construction above described are not important so far as my present invention is-concerned. I have merely illustrated them to indicate how my improvements areassociated with an ordinary cylindrical platen and parts of the mechanism immediately associated theretherewith. The main platen A may be of the usual construction, being cylindrical in form with a core an covered with rubber or other relatively soft material a. The platen shaft of extends through the side plates of the carriage and is provided with finger pieces or knobs a as usual. The right hand end of the platen has secured to it a circular plate M formed with a boss m. the end of which abuts the adjacent side piece B of the carriage. The platen shaft extends through the plate M and through the boss known construction comprising among other things a cylindrical member a turning at all times with the laten and a member 01- associated with cevices for controlling the spacing of the lines of print.

The auxiliary platen O is in the form of a narrow strip of suitable rigid material, such as metal, and extending from end to end of the main platen and curved transversely to correspond with the contour of the main platen so that it may lie close thereto and in frictional contact therewith at all times throughout its entire length and from its upper to its lower edge. Both the inner and outer surfaces of the auxiliary platen are smooth in order that good sharp type impressions may be. made and that it may be moved when desired around the axis of the main platen but independently thereof.

The auxiliary platen is so mounted that it 95 may turn with the main platen about the longitudinal axis thereof from inactive to active postion or vice versa while in close contact with the main platen or may move about such axis independentlyof the main I provide a support Q, for the auxiliary platen comprising a dished central portion 9 formed with a lateral extension 1 carrying an arm Q2 to which the inner bent portion 0 at the right handend of the auxiliary platen is secured. The centralportion g of the support is provided with a central opening which surrounds and is seated in the groove or recess 7n. formed in the outer end of the boss 422... 'As shown in Figure 4 the support Q is mounted to turn between the grooved shouldered portion of the boss and the adjacent side plate of the'carriage, at the same time preventing lateral displacement of the auxiliary platen.

The opposite end of the auxiliary platen has an lnturned end portion 0 secured. to a ring R which is mounted'toturn about the axis of the main platen while supported between the members at and n. The specific 125 supports for the auxiliary platen shown are not essential but they have been found serviceable in applying the invention to a' machine of the Royal type.

The auxiliary platen is held throughout'130 its entire length close to the main platen and as hereinbefore described may be either turned with the main platen or independent thereof. It is important that suitable detent mechanism be provided to hold the auxiliary platen in the position to which it is set and for this purpose I have provided devices which have been found to be most efiicient in practice. The support Q. it will be observed, is formed with a peripheral portion having a curved edge concentric with the axis of the platen and at opposite ends of which are formed notches 00, as to receive a detent pawl. The ring R on the opposite end of the platen is formed with notches 3 1 for a similar, purpose.

Preferably two detent pawls T and T are employed, one of which co-operates with the detent member Q and the other'with the detent member R. Preferably these pawls are connected by a horizontally arranged rod U extending across the machine beneath the paper table. The pawls are so mounted that they are always moved simultaneously and to the same extent. The opposite ends of the rod U are preferably mounted to turn in ears 7) extending upwards from the carriage side plates, but other means for supporting the rod may be provided. The rod may be so mounted as to be a permanent part of the machine carriage or it may be detachably connected therewith, although preferably the rod with its detent pawls are made a permanent part of the machine as they do not in any way interfere with other portions of the mechanism.

The pawls T, T have teeth 15, t formed ontheir front ends adapted to engage the notches w, m, 3 y and they are formed with projections or stops t which strike against the top edges of the side plates and thus limit their downward'moveme'nt while engaging the notches. Springs W tendto draw the toothed ends of the pawls downwvardly until the downward movement is arrested by the stops t above referred to. The upward movement of the pawls may be limited by a stop t formed on one of the pawls or on both of them if preferred. A- handle or finger piece for lifting the pawls simultaneously is indicated at V. This is preferably placed at the left hand side of the machine so that the hand of the operator may be applied to the knob or finger piece a at the right hand side of the machine to turn the main platen, while the left hand of the operator raises the pawls simultaneously to permit the'main platen to be turned to bring the auxiliary platen into active or inactive position. 7

While the auxiliary platen is being moved from one position to another, the pawls ride on the curved portions 9 and r of the supports between the detent notches. When the pawls engage in the notches they look the mechanism firmly and in such manner as to hold the auxiliary platen with precision close to the main platen throughout its entire length so that a firm and rigid backing is provided for manifold purposes. If the auxiliary platen were allowed to-sh-ake or to spring back and forth on the main platen, good printing results could not be obtained. It will be observed by reference to Figure 2 that the front and rear walls of the notches m, :r and by reference to Figure 3 that the front and rear walls of the notches? are straight and parallel and when in active position are tangential to the axis of the main platen. The walls of the teeth on the detent pawls are similarly shaped so that when the pawls are engaged in the notches no movement of the auxiliary platen can take place, but the main platen is free to turn in the usual way. Without positive locking means of this sort the main platen could not be turned without moving the auxiliary platen in view of the close contact of the auxiliary platen with the main platen which I have found to be a most desirable feature of the invention.

In order to limit the movement of the auxiliary platen, i. e., to prevent overthrow in either direction, the support Q is formed with a projection 2' which strikes against the end of the pawl T when the limit of the backward movement is reached. The'support Q. is also formed with a projection 2 which serves a similar purpose when the limit of the forward movement is reached. These projections are disposed close to the notches w, w and serve as locators for the auxiliary platen.

The details of the type action are not illustrated in the drawings. As before stated, noise reducing type actions of the kind indicated in Figures 1 and 2 may be employed or theordinary type action like that shown in Figure 9 may be used.

The auxiliary platen may conveniently be used as an erasing plate being moved to any desired or convenient position on the main platen for this purpose.

In Figure 8 I have shown an auxiliary platen provided with a letter space scale which may be conveniently used in many kinds of work, especially in work of the kind known as split billing.

V'Vhile the auxiliary platen is held very close to the main platen, it is made so thin, light and smooth and is made to conform so closely to the shape of the main platen that when the auxiliary platen is in use or when not in use it does not act unduly as a brake to the main platen or in any way interfere with its normal movement. It can in an instant be brought into active position or withdrawn therefrom.

In some of the following claims where reference is made to a platen in the combieral service, of a noise-reducing type action and an auxiliary platen of relatively hard material adapted to be held in the line of print for multiple manifold purposes, as such subject matter is covered by several claims to this broad feature and amplifications thereof in my application for patent filed June 22, 1922.

I claim as my invention 1. An auxiliary platen for typewriting machines, comprising a strip of suitable 'rigid material co-extensive in length with that of the main platen, and curved on opposite sides to conform to the curvature of the main platen, in combination with supports at its ends for holding it to turn about the longitudinal axis of the main platen while in contact therewith and which are provided with detent devices.

. 2. An auxiliar platen for typewriting machines comprising a strip of suitable rigid material conforming in length and curvature with the main platen and having smooth inner and outer sides in combination with supports at its ends for holding it in frictional engagement with the main platen to turn about the longitudinal axis thereof, either with the main platen when the latter is turned, or independent thereof.

3. In a typewriting machine the combination of a cylindrical platen, an auxiliary platen held in frictional engagement therewith and movable therewith and thereby about its axis and also movable independently thereof, and means for locking the auxiliary platen in active and inactive positions and for preventing overthrow beyond these positions.

4. In a typewriting machine, the combination of the main cylindrical platen, and

an auxiliary platen comprising astrip of suitable rigid material co-extensive in length and curvature with that of the main platen, and having smooth inner and outer sides in combination with supports at its opposite ends for holding it to turn about the longitudinal axis of the main platen, one of said supports having a curved peripheral portion with detent notches at opposite ends adapted to engage a detent pawl.

5. An auxiliary platen for typewriting machines, comprising a strip of suitable rigid material, co-extensive in length with that of the main platen and curved on opposite sides to conform to the curvature of the main platen, in combination with supports at its ends for holding it to turn about the longitudinal axis of the main platen and Which are provided with connected detent devices in alignment with each other at opposite ends of the platen.

6. In a typewriting machine the combination of the main cylindrical platen, an auxiliary platen mounted to turn about the longitudinal axis thereof and provided with detent members, detent pawls, pivotally mounted in rear of the platen and adapted to engage the detent'members thereof, and means connecting the pawls at opposite sides of the machine whereby they may be simultaneously lifted.

7. In a typewriting machine, the combi-' nation of a main cylindrical platen, an auxiliary platen mounted to turn about the lon-' gitudinal axis thereof, detent members con nected with the opposite ends of the auxiliary platen, detent pawls pivotally mounted'in rear of the platens and provided with springs for drawing them towards the detent members of the platen, means for limiting the movement of the pawls after engagement with the detent members of the platen and means for simultaneously raising the pawls.

8. In a typewriting'machine, the combination of the main cylindrical platen, an

auxiliary platen mounted to move about the longitudinal axis thereof, detent members at opposite ends of the auxiliary platen, detent pawls adapted to engage said detent members, a connection between the two pawls and means for limiting the movement of the pawls when they are withdrawn from engagement with the detent members of the platen.

9. In a typewriting machine, the combination of the main cylindrical platen, an auxiliary platen mounted to turn about the longitudinal axis thereof. a detent member. at one end of the platen, having detent notches formed with tangential walls, and a detent pawl adapted to engage said notches, having front and rear walls corresponding with those in the notches in the detent member of the platen.

10. In a typewriting machine. the combination of a main cylindrical platen, an auxiliary platen mounted to turn about the longitudinal axis thereof, a detent member at one end of the platen formed with notches for locating the active and inactive positions of the auxiliary platen. and a pawlhaving a toothed front end adapted to closely fit either of said notches with its front and rear walls conforming to the front and rear walls ofsaid notches, and projection on the detent member adapted to engage said detent pawl to' limit the movement of the auxiliary platen, when turned about the axisof the main platen.

11. In a typewriting machine the combination of amain platen, an auxiliary platen associated therewith and movable to active and inactive positions, said auxiliary platen being provided with letter space scale gradmachines, comprlsing a strip nations for the purpose specified.

ewriting suitable rigid material co-extensive in length with 12. An auxiliary platen for ty that of the main platen and curved on opposite sides to conform to the Curvature of the main platen and Whichis provided with a margin locating scale and with supports at its ends for holding it to turn aboutthe longitudinal axis of the main platen from a position in rear of the axis of the platento' a position across the line of print.

, 13. In a typewriting" machine, the combination of a main cylindrical platen and an auxiliary platen associated therewith and frictionally held thereby in a plurality of positions, said auxiliary platen having'a smooth outer'surface and being movable 1- about the axisof the main platen from a position in which it serves as a backing during' manifolding to another position in which it serves as an erasing plate.

14:. In a typewriting machine, the combination of a main platen and an auxiliary platen associated therewith and movable thereby to active and inactive positions-relatively to the printing point.

15. In a typewritlng machine the combination of a main platen and an auxiliary platen associated therewith and movable thereby to active and inactive positions relatively to the printing point, means for holdingthe auxiliary platen in active position, and devices for preventing overthrow of the auxiliary platen when moved from tion to the other.

In testimony whereof, I have hereunto subscribed my name.

' EDWARD B. HESS.-

one posl- 

